In two patients with massive pulmonary embolism and cardiogenic shock requiring mechanical ventilation and prolonged external cardiac massage, occluded pulmonary arteries were recanalized by primary mechanical fragmentation of thrombi using a percutaneously inserted catheter followed by fibrinolytic therapy. The hemodynamic and respiratory parameters rapidly and greatly improved. Pulmonary angiography before discharge revealed normal results in both patients. No central neurological abnormalities were detected. It is concluded that patients with cardiogenic shock due to massive pulmonary embolism may benefit from immediate mechanical thrombus fragmentation followed by fibrinolysis when thrombolysis or surgical embolectomy are strictly contraindicated or not available.